A changing of the PR guard is happening at Goldman Sachs just as the company's reputation has "received another nail in the coffin" after the very public ranting of a former executive.

A departing executive in the firm's London office accused Goldman in an Op-Ed in The New York Times on Wednesday of losing its moral compass and being overtaken by a greed-infested corporate culture.

"I can honestly say that the environment now is as toxic and destructive as I have ever seen it," Greg Smith, who quit as head of the firm's equity derivatives business in Europe, wrote in an opinion piece.

In the wake of the Op-Ed's publication, Lloyd Blankfein, Goldman's chief executive, suggested that Smith may have a grudge against the company.

"In a company of our size, it is not shocking that some people could feel disgruntled," Blankfein and another top executive wrote in response. "But that does not and should not represent our firm of more than 30,000 people."

As Goldman puts its damage-control plan into place, the Times' DealBook site reported that the company has hired Richard Siewert Jr., a former counselor to Treasury Secretary Timothy Geithner, as global head of corporate communications. He will replace Lucas van Praag.

Goldman Sachs did not respond to numerous inquiries from PRWeek to confirm the hire. Van Praag is the sixth PR staffer to leave Goldman in the past year.